using System.Collections.Generic;
using System.Windows.Forms;

namespace WindowsFormsApplication1 {
    public partial class Form1 : Form {
        public Form1() {
            InitializeComponent();
        }
        private void Form1_Load(object sender, System.EventArgs e) {
            Employee emp1 = new Employee() { JobTitle = "Chief Executive Officer", Name = "Bruce Cambell", City = "Oaks" };
            Employee emp2 = new Employee() { JobTitle = "Information Services Manager", Name = "Cindy Haneline", City = "Vista" };
            Employee emp3 = new Employee() { JobTitle = "Database Administrator", Name = "Andrea Deville", City = "Aurora" };
            Employee emp4 = new Employee() { JobTitle = "Application Specialist", Name = "Anita Ryan", City = "West" };
            Employee emp5 = new Employee() { JobTitle = "Network Manager", Name = "Anita Cardle", City = "Glendale" };
            Employee emp6 = new Employee() { JobTitle = "Network Administrator", Name = "Andrew Carter", City = "Moline" };
            Employee emp7 = new Employee() { JobTitle = "Marketing Manager", Name = "Carolyn Baker", City = "Longview" };

            emp1.Subordinates = new List<Employee>() { emp2, emp7};
            emp2.Subordinates = new List<Employee>() { emp3, emp4, emp5 };
            emp5.Subordinates = new List<Employee>() { emp6 };

            List<Employee> dataSource = new List<Employee>();
            dataSource.Add(emp1);

            treeList1.ChildListFieldName = "Subordinates";
            treeList1.DataSource = dataSource;
        }
    }

    public class Employee {
        public Employee() {
        }
        public string JobTitle { get; set; }
        public string Name { get; set; }
        public string City { get; set; }
        public IList<Employee> Subordinates { get; set; }
    }
}

Partial Public Class Form1
    Public Sub New()
        InitializeComponent()
    End Sub

    Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim emp1 As Employee = New Employee() With {.JobTitle = "Chief Executive Officer", .Name = "Bruce Cambell", .City = "Oaks"}
        Dim emp2 As Employee = New Employee() With {.JobTitle = "Information Services Manager", .Name = "Cindy Haneline", .City = "Vista"}
        Dim emp3 As Employee = New Employee() With {.JobTitle = "Database Administrator", .Name = "Andrea Deville", .City = "Aurora"}
        Dim emp4 As Employee = New Employee() With {.JobTitle = "Application Specialist", .Name = "Anita Ryan", .City = "West"}
        Dim emp5 As Employee = New Employee() With {.JobTitle = "Network Manager", .Name = "Anita Cardle", .City = "Glendale"}
        Dim emp6 As Employee = New Employee() With {.JobTitle = "Network Administrator", .Name = "Andrew Carter", .City = "Moline"}
        Dim emp7 As Employee = New Employee() With {.JobTitle = "Marketing Manager", .Name = "Carolyn Baker", .City = "Longview"}
        emp1.Subordinates = New List(Of Employee)() From {emp2, emp7}
        emp2.Subordinates = New List(Of Employee)() From {emp3, emp4, emp5}
        emp5.Subordinates = New List(Of Employee)() From {emp6}
        Dim dataSource As List(Of Employee) = New List(Of Employee)()
        dataSource.Add(emp1)
        TreeList1.ChildListFieldName = "Subordinates"
        TreeList1.DataSource = dataSource
    End Sub
End Class

Public Class Employee
    Public Sub New()
    End Sub
    Public Property JobTitle As String
    Public Property Name As String
    Public Property City As String
    Public Property Subordinates As IList(Of Employee)
End Class

using DevExpress.XtraTreeList;
using DevExpress.XtraTreeList.Columns;
using System.Collections;
using System.Windows.Forms;

public class Node : TreeList.IVirtualTreeListData {
    protected Node parentCore;
    protected ArrayList childrenCore = new ArrayList();
    protected object[] cellsCore;

    public Node(Node parent, object[] cells) {
        this.parentCore = parent;
        this.cellsCore = cells;
        if (this.parentCore != null) {
            this.parentCore.childrenCore.Add(this);
        }
    }
    void TreeList.IVirtualTreeListData.VirtualTreeGetChildNodes(VirtualTreeGetChildNodesInfo info) {
        info.Children = childrenCore;
    }
    void TreeList.IVirtualTreeListData.VirtualTreeGetCellValue(VirtualTreeGetCellValueInfo info) {
        info.CellData = cellsCore[info.Column.AbsoluteIndex];
    }

    void TreeList.IVirtualTreeListData.VirtualTreeSetCellValue(VirtualTreeSetCellValueInfo info) {
        cellsCore[info.Column.AbsoluteIndex] = info.NewCellData;
    }
}

Imports System.Collections
Imports DevExpress.Data
Imports DevExpress.XtraTreeList
Imports DevExpress.XtraTreeList.Columns

Public Class Node
    Implements TreeList.IVirtualTreeListData
    Protected parentCore As Node
    Protected childrenCore As New ArrayList()
    Protected cellsCore() As Object

    Public Sub New(ByVal parent As Node, ByVal cells() As Object)
        Me.parentCore = parent
        Me.cellsCore = cells
        If Not (Me.parentCore Is Nothing) Then
            Me.parentCore.childrenCore.Add(Me)
        End If
    End Sub

    Sub VirtualTreeGetChildNodes(ByVal info As VirtualTreeGetChildNodesInfo) _
    Implements TreeList.IVirtualTreeListData.VirtualTreeGetChildNodes
        info.Children = childrenCore
    End Sub

    Sub VirtualTreeGetCellValue(ByVal info As VirtualTreeGetCellValueInfo) _
    Implements TreeList.IVirtualTreeListData.VirtualTreeGetCellValue
        info.CellData = cellsCore(info.Column.AbsoluteIndex)
    End Sub

    Sub VirtualTreeSetCellValue(ByVal info As VirtualTreeSetCellValueInfo) _
    Implements TreeList.IVirtualTreeListData.VirtualTreeSetCellValue
        cellsCore(info.Column.AbsoluteIndex) = info.NewCellData
    End Sub

End Class

public partial class Form1 : Form {
    public Form1() {
        InitializeComponent();
        InitData();
    }

    void InitData() {
        Node tlDataSource = new Node(null, null);
        // The first root node. 
        Node rootNode1 = new Node(tlDataSource, new string[] { "CEO", "High" });
        Node node1 = new Node(rootNode1, new string[] { "Sales", "Normal" });
        Node node2 = new Node(node1, new string[] { "Direct vs Online Sales Comparison Report", "High" });
        Node node3 = new Node(node1, new string[] { "Training Events", "Low" });
        // The second root node. 
        Node rootNode2 = new Node(tlDataSource, new string[] { "HR department", "High" });
        Node node4 = new Node(rootNode2, new string[] { "Update Employee Files with New NDA", "High" });
        TreeListColumn colName = new TreeListColumn();
        colName.Caption = "Name";
        colName.VisibleIndex = 0;
        TreeListColumn colRank = new TreeListColumn();
        colRank.Caption = "Rank";
        colRank.VisibleIndex = 1;
        treeList1.Columns.AddRange(new TreeListColumn[] { colName, colRank });
        treeList1.DataSource = tlDataSource;
    }
}

Partial Public Class Form1
    Public Sub New()
        InitializeComponent()
    End Sub

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        InitData()
    End Sub

    Sub InitData()
        Dim tlDataSource = New Node(Nothing, Nothing)
        Dim rootNode1 = New Node(tlDataSource, New String() {"CEO", "High"})
        Dim node1 = New Node(rootNode1, New String() {"Sales", "Normal"})
        Dim node2 = New Node(node1, New String() {"Direct vs Online Sales Comparison Report", "High"})
        Dim node3 = New Node(node1, New String() {"Training Events", "Low"})
        Dim rootNode2 = New Node(tlDataSource, New String() {"HR department", "Normal"})
        Dim node4 = New Node(rootNode2, New String() {"Update Employee Files with New NDA", "High"})
        Dim colName As TreeListColumn = New TreeListColumn()
        colName.Caption = "Name"
        colName.VisibleIndex = 0
        Dim colRank As TreeListColumn = New TreeListColumn()
        colRank.Caption = "Rank"
        colRank.VisibleIndex = 1
        TreeList1.Columns.AddRange(New TreeListColumn() {colName, colRank})
        TreeList1.DataSource = tlDataSource
    End Sub
End Class